Automatic ignition cutoff system



Aug. 24, 1943. c. N. REAVIS 2,327,558

AUTOMATIC IGNITION CUT-OFF SYSTEM Filed April 18, 1941 5 Sheets-Sheet l Inventor Charles N Bea/v1.5

Attorney;

Inventor 3 Sheets-Sheet 2 CMrZes N Rear/Z5 B) W C. N. REAVIS Filed April 18, 1941 AUTOMATIC IGNITION CUT-OFF SYSTEM TO 1.51 I 0756 1) RB Aug. 24, 1943.

A Nor/1 Aug. 24, 1943. c. N. REAVIS AUTOMATIC IGNITION CUT-OFF SYSTEM Filed April 18, 1941 3 Sheets-Sheet 5 Char/e5 N Rea/Via Patented Aug. 24, 1943 UNITED STATES PATENT OFFIQE AUTOMATIC IGNITION CUTOFF SYSTEM Charles N. Reavis, Raleigh, N. 0. Application April 18, 1941, Serial No. 389,260

Claims.

My invention relate to improvements in means for protecting automobile and other internal combustion engines by automatically cutting off the ignition and thereby stopping the engine whenever a failure of the lubrication system or lack of oil therein occurs or when the water in the cooling system falls below a safe level, and

the primary object of my invention is to provide such means in simple and practical form adapted for easy installation.

Another important object of my invention is to provide a system of the character indicated which is adapted for connection in the primary ignition circuit without the cutting of any of the wires thereof or other disarrangement of the usual disposition and functioning of the ignition system. I

Other important objects and advantages of my invention will be apparent from a reading of the following description of the appended drawings, wherein for purposes of illustration, a preferred embodiment of my invention is shown.

In the drawings:

Figure 1 is a fragmentary longitudinal vertical sectional view taken through the motor compartment of an automobile and tion of the present invention.

Figure 2 is an enlarged longitudinal sectional view taken through the casing of the oil failure showing adaptaresponsive component of the invention, and frag- I mentarily through the casing of the cooling medium affected component, and showing diagrammatically their electrical connections to the ignition system.

Figure 3 is a fragmentary horizontal sectional view taken through Figure 2 along the line 33 and looking downwardly.

Figure 4 is an enlarged fragmentary vertical longitudinal sectional view taken through the lower right hand portion of casing 6 of Figure 2.

Figure 5 is a side elevational view of the cooling medium affected component, and

Figure 6 is a right hand end elevational view of Figure 5.

Figure 'l is an enlarged longitudinal sectional view taken through the casing of the water failure responsive component of the invention.

Referring in detail to the drawings, the numeral 5 generally designates the oil pressure failure responsive unit which involves a suitable metal casing 6 preferably in rectangular form for mounting on and grounding to the front of the dashboard l or other suitable place in the motor compartment 8. A fitting 9 depending from the bottom of the casing 6 is arranged for connection to the motor lubricating system oil pressure line H). Inside the casing 6 an oil pressure responsive bellows I I has its lower end connected in communication with the fitting 9. The upper end of the bellows has a lug l2 inserted upwardly in the opening [3 in the horizontal insulated arm M which is pivoted at I5 on a lug IS on one end of the casing 6. A stop lug I4 to limit upward movement of the arm 14 projects from the back of the casing. Between the hole l3 and the pivot [5 a vertical eye bolt ll traverses the arm 14 and has a contractile spring l8 stretched between its eye and an anchor 19 on the bottom of the casing. The free end of the said arm is notched at 20 to freely accept the lug 2! on the adjacent end of the casing to steady the operation of the arm. A binding post contact 22 traverses the arm l4 adjacent the said free end for electrical engagement with a companion stationary binding post contact 23 which is mounted through a lug 24 on the adjacent end of the casing. An insulated binding external post 25 traverses the same end of the casing and is connected to the contact 23 by a bar 26.

The binding post contact 22 on the arm 14 is connected by a flexible wire 21 to an insulated external binding post 28 traversing the right hand end of the casing 6 below the lug I6. A horizontal helical electrical heating element 29 is suspended between a post 29 electrically connected to the casing 6, and hence grounded, and the binding post 28.

Horizontally supported immediately below the heating element is the time delay element comprising a pair of bimetallic strips 30 and 3|. These strips are supported in vertically spaced and insulated relation on the insulating block 32 mounted on the end of the casing, with their contact terminals normally spaced at a. distance of about A of an inch. The lower strip 3| is connected by a wire 3| to the external insulated binding post 33 which traverses the bottom of the casing. The upper strip 30 is grounded at 30' to the casing B. One reason the strips are both bimetallic in character is to provide against the unwanted closing of the strips during an onset of warm weather, their spacing having been adjusted for cold weather operation. By using two similar bimetallic strips the warp of the strips is similar and the original spacing automatically maintained while the heater 29 heats the upper strip 30 sufiiciently to cause it to warp relative to the lower strip 3| and electrically engage their contact terminals and close the circuit therethrough.

The '11 pressure failure responsive unit described above is connected in the ignition system of the motor 34 by connecting a wire to a point 36 between the voltage regulator or relay 3? and the field coils of the generator 38. Another wire 39 is connected between the binding post 33 and the primary side of the ignition coil 4| direct or to the ungrounded side d2 of the circuit breaker 43, whichever is more convenient. Another wire 44 connects between the binding post 23 and the ungrounded side of a suitable signal such as a bulb whose ofiice is to warn the driver, in the event of a loss of oil pressure and/or of a low cooling medium level, before the actual cut-out of the ignition system occurs, so that the driver may pull over to the curb or into a service station before the motor is rendered inoperative.

It will appear from the foregoing that whenever the oil pressure in the oil line It drops below the pressure for which the device is adjusted, the bellows ll will collapse, and, aided by the spring Hi the arm i l will subside from an elevated position to the depressed position shown in Figure 2 of the drawings and engage the contacts 2'2 and 23. This energizes the heater 29 and operates thesig-nal- 45. After the predetermined time delay, such as 45 seconds, the strips 30 and 31' close and thereby cut oif the current supply to the circuit breaker 43 and the ignition coil, thereby stopping the motor. v

The connection of the wire 35 is made at the described point to insure the inoperativeness of the device when the motor is idling at a low speed and oil pressure is below normal, as in waiting for a traffic light or while parked, and at such a low speed as to fail. to turn the generator fast. enough to. close the points in the voltage regulator or relay 3?. It is to be observed that the connections to. the circuit breaker and/or the primary of the ignition coil are made simply by loosening the binder nuts, and retightening them, thereby. eliminating any cutting ofwires, or other damageor change tothe original condition of the ignition system. 7 i i The cooling medium affected component which is generally designated 59 comprises a suitable.

oflthe block it. are longitudinallystaggered tosupport spaced vertical spring contact fingers '59" andtilzlwhich' have facing contacts on their upper ends; 7

.Ae hinge til mounted on the bottom of the'casing ti near the'b-lock 58' constitutes the pivotal support for the tiltab-l'e. generally-rectangular.

tank 62"50 whose adjacent lower corner the hinge is attached. When. normally full of coolingmediumfrom the radiator; tank 54theztank 62 rests:

upon; a felt mat, 63 on the bottom of the casing; rkh. r

'A, contractile spring 674i is stretched between,

the eye on the casing; end and the; eye (-26: on theslanted tanklend whereby thetank: Eiilis tilted upwardly ina: left hand: direction: whenever" the cooling medium in the radiator tank 54 subsides determined level.

below a selected level and cooling medium leaves the tank 52 by the drain pipe Bl.

The tank 62 is located at such an elevation that the bottom of the tank 62 will be near or above or below the bottom of the radiator tank 54 but always above the level of the head of the motor 34, so that whenever through any cause the level of the water in the radiator and radiator tank 54 goes below the predetermined point the tank 62 will be substantially emptied of cooling medium and pullediup into tilted position by spring 64. A rigid adjustable linkage 68 operatively connects the adjacent end of the tank 62 with the spring contact element 66 so that the contact element is engaged with the contact element 59 in the uptilted position of the tank and separated from the contact element 59 is the normal horizontal position of the tank 6-2.

Fluid connection with the tank 62 are pro vided by the upper and lower tubes 69 and El, respectively, which project from the side wall of the tank through slots torn-red in the sidewall ofthe casing St. The casing has a removable cover. The lower or gravity drain tube til is connected by a hose Til toa depressed part of the cooling system, such as the lower radiator hose 'H", while the upper tube S tis connected by a pipe 12 tothe radiator tank 5d at the pre- The contact Bo is connected to the wire at 1'3 while the contact 553 i s-connectedto the binding post 2%, whereby thecon-tact points 22 and 23 are shunted whenthe points 59' and come together when a. low water" condition obtains in the radiator, thereby cutting off the ignition system. a

Although I have shown and described herein a preferred embodiment of my invention it is to be understood that I do not wish to limit the application of my inventionthereto, except as may berequired by the scope of the subjoined' claims.

Having described the invention, what is claimed asnew is:

1 In a devicefor cutting off the ignition systern of aninternalcombustion engine, said device comprising an oil pressure failure responsive component comprising a circuit closer maintained open by normal on pressure and adapted toclos'e in theabsence of normal oil pressure,

said circuit cloeer having" one" side thereof connested to thegeneratcr of the-ignition system at a -point between the field coils-and thevolta'ge regulator of said generator and having it's re'-' mainingside connectedto the battery of" said ignition system, whereby closing" of'said' circuit closer is precluded during low oil'pressure in'ci dent to idlingof'said engine;

2. A- device according to claim 1' wherein said" ci-rcuitcloser comprises a bellows connected to the engine oil pressure line; a pivoted arm normally elevated bysai'di bellows" due to its expanded condition, a first contact on said" arm, a second contact supported for engagement' by said'fi'rst' contact only; in' the depressed position of saidarm. 2 c

3. Irr a device for cutting oil the ignition system of an internal combustion engihe havlng a pressure-oiling system; said oilingsystem having an oil pressure responsive element, 'a first'normallyopen circuit closer connected in'jsaid syscircuit closer; said second circuit closer-comprising thermostatic circuit grounding contactors arranged to close when heated, electrical heating means for said thermostatic contactors and connected in said system for energization only while said first circuit closer is in closed position, said first circuit closer being arranged to close upon a drop of the oil pressure below a predetermined level and energizesaid electrical heating means, thereby effecting delayed closing of said second circuit closer and grounding of the ignition circuit.

4. In a device for cutting off the ignition system of an internal combustion engine having a pressure oiling system having an oil pressure responsive element, said ignition system including a battery-generator component wherein the output of the generator to the battery is controlled by a voltage regulator, said device comprising a switch operatively connected to said oil pressure responsive element, said switch being electrically connected in said system at a point between the battery and the voltage regulator so as to be inefiective for deenergizing the ignition circuit while the engine is idling at low speed and the oil pressure is correspondingly below normal.

5. In a device for deenergizing the ignition system of an internal combustion engine having a pressure oiling system having a pressure responsive element, said ignition system including a primary circuit including a battery-generator component wherein the output of the generator to the battery is controlled by a voltage regulator, said device comprising a casing supporting and enclosing said pressure responsive element, said element comprising a vertical member arranged to occupy an elevated position during normal oil pressure and a depressed position during low oil pressure in said oiling system, a horizontal bar pivoted at one end on said casing with its opposite end overlying said vertical member, a first contact on and insulated from the free end of said horizontal bar, a companion second contact below said first contact, said second contact being mounted in and insulated from said casing, said first and second contacts being disengaged while said vertical rnember is in an elevated position responsibe to normal pressure n the oiling system, one of said first and second contacts being electrically connected in said primary circuit at a point between the battery and the voltage regulator so that closing of the said first and second contacts is ineffective to deenergize the ignition circuit while the engine is idling at low speed and the oil pressure is correspondingly below normal, a shunt circuit including an electrical heating coil in said casing and connected around said first and second contacts, a pair of normally separated thermostatic contact arms lying spacedly along said heating coil and arranged to warp when said heating coil is energized and electrically engage each other after a short delay thereby effecting delayed opening of said primary circuit.

CHARLES N. REAVIS. 

